Tie-rod-withdrawing jack.



y R. SHARP.

TIE ROD WITHDRAWING JACK. APPLICATION FILED DEC. 4, l9l8.

W/T/VESSES Patented Mar. 25,1919.

PATENT onirica.

ROBERT SHARP, OF TUCKAHOE, NEW YORK.

TIE-ROD-WITHDRAWING- JACK.

Application filed December 4., 1918.

To all whom t may concern:

Be it known that I, ROBERT SHARP, a citiprovement in the method offorming con-v crete constructions in those situations where the moldboards of the form are tied together by metal rods embedded in theconcrete and which usually remain in position at least until theconcrete -hasset The primary object of the invention is to provide aconcrete mold construction, and particularly a tie rod therefor, all theparts of which mold construction maybe used repeatedly without thenecessity of reforming the parts7 and incidental to this primary objectit is desirable to provide in such a construction, a tie rod for theconcrete which will permit the form boards to be removed earlier thanthese boards can be removed Linder present practices.

Broadly the invention contemplates a form of tie rod which will not onlyact to tie the boards together durino` the pouring and initial stages ofthe setting operation but which will also tie together the outerportions where the setting process has farthest advanced. With this formof concrete tying rod it is possible, as soon as these outer shells ofconcrete have a rigidity suiiicient to hold the configuration of thestructure to remove the boards so that they may be used iii-anotherlocation.

It has been suggested that tie rods for the molds be made smooth andwhen the concrete has set sufficiently to permit the removal of the formto withdraw the rods by means of a turn-buckle arrangement one threadedportion of which bears on the outer wall of the mold and another similarportion engages a crimped portion of the smooth rod.

In the improved method, herein disclosed, however, it is necessary toallow the rods to remain in the concrete after the premature removal ofthe boards and especially where the rods are allowed to remain for anymaterial time the concrete adheres to the rod tov such an extent thatthe adoption of the Specification of Letters Patent.

Patented Mar. 25, 1919.

Serial No. 265,292.

suggested use of a turn-buckle to pull the rods loose is impossible andimpractical.

Accordingly, the invention features a powerful rod withdrawing devicecapable of loosening the adhesion between the rod and concrete anddesigned to Withdraw the rod rapidly and without bending after it hasbeen loosened from its original position in the concrete.

With the concrete exposed any attempt to pull the tie rod longitudinallyout of position would result in the rod bringing with it some of theconcrete. This is avoided by first giving the rod a slightly rotarymovement about its own axis soa that the initial withdrawing movement issomewhat in the nature of a -screw action. When loosened the rod may bewithdrawn longitudinally without any material damage to the concrete.

In Such operations there is grave danger of bending the rods andespecially where the rods are screw-threaded, any such bending wouldminimize the possibility of immediately reusing the rods in another partof the structure.

Accordingly, another object of the invention is to provide a guidingmeans for engaging as much of the tie rod as possible, taking intoconsideration the commercial necessity of making the device of the leastpractical length so as to apportion the portable weight of material intoa minimum number of massive parts rather than feature a long screwingdevice.

Various other objects and advantages of the invention will be in partobvious from an inspection of the accompanying drawings and in part willbe more fully set forth in the following particular description of oneform of mechanism embodying my invention, and the invention alsoconsists in certain new and novel features of construction andcombination of parts hereinafter set forth and claimed.

In the accompanying drawings Figure l Vis a view in vertical sectiontransversely of a concrete wall with the form boards in position, tiedtogether by means of a tie rod constituting a part of a preferred formof my invention;

Fig. Q is a perspective view of the wall shown in Fig. l with the moldboards removed and showing the parts of a preferred form of my inventionin operative engagement with one of the rods to withdraw the same; and

F ig. 3 is a view in side elevation of the jack constituting a part ofthe withdrawing means shown in Fig. 2.

In the following description and in the claims, -parts will beidentified by specific names for convenience of expression lbut they areintended to be as lgeneric in their application to similar parts as theart will permit.

There is shown a wall A ot concrete or similar self-hardening plasticmaterial which has been poured into the form and between the boards Bthereof. During the` pouring operation and during the initial periods ofthe setting operation the boa-rds l are held in position by means ot tierods l() which extend beyond opposite faces of the boards B and theboards are held in position by means ot' nuts C in threaded engagementwith the rods 10. For this purpose the end portions of the rods areprovidedwith screw threads 1l and in one phase of the invention thethreads are arranged so as to extend into the outer portions of t-heconcrete as shown in Figs. 1 and 2. These threads are'arran'ged to formcorresponding threads 1Q, in the outer yportions of the concrete as itbecomes set. As is known the concrete sets progressively Yfrom the outerexposed sides inwardly toward vthe interior of the concrete structureand by connecting these "set portions it possible to utilize themold-board-tie-rods for the purpose ot' tying `together the outerportions of the wall A. There is therefore formed, in effect, a pair ofspaced apart and tied together shells whichwill maintain theconfiguration of the wall until the concrete has entirelyl set. By thismeans it is possible to remove the mold boards shortly after the wall ispoured. This exposes the outer sidesI of the wall earlier than usual andtends to facilitate the rapid setting of the concrete. The lrodstherefore remain in the concrete longer than has been usual in priorsituations where it is suggested t0 withdrav,v the rods prior to or atthe same time that the mold boards areremoved.

The mechanism for withdrawing' the rods features a massive constructionmade sulliciently light'in weight so as to be handled by one man butwith the metal so proportioned as to give the'maximum resist-ance tobending 'or distortion when in use. Feat-uring the simplicityofconstruction there ris shown a=screw jack 14;7 formed primarily ottwoscrew parts. One ofthe partsis a hollow casting flha'vi-ng one endenlarged to form a flange 16 for engaging theconcrete overamateiial areathereof andwhich a is held against rotary movement by the frictionalengagement with the concrete engaging surface 17 forming the adjacentside of the concrete construction. This bearing element forms the femalemember of the screw combination and Vhas a bore 18 of relatively largediameter ovided with internal screw threads prefera ly of the squarethreaded type which have been found most effective to give the requisitestrength to the threaded part of `this rodv withdrawing jack. The othermember of the screw connection is relatively long and isl provided withabore 19 4extending "axially therethrough. This bore has a diametersuiicient to acconimodate the rod 10 passed therethrough as shown inFig. 2. In its most perfected construction the rod should have a slidingtit in the bore so that the rod would beguided tor the entire length ofthis member, but as these rods are usually made up ot rough stock'thereshould be sufficient clearance between the rod and'shiftablemember topermit a free movement of the rod but this clearance should'be no niorethan necessary so that the membermay actas a guide Jfor engagingttl'iegreatest possible length of rod, and thus tend to prevent distortion ofthe rod in' the wit-l'idrawal of the same fromthe lconcrete. Y

This member 1s provided centrally thereof witha massivey head 20 havingopenings Q1 extending laterallytherethrough to accommodate a longcrow-bari@ or similar leverage tool necessary when suchdevices are-actuated by manual force.

AWhere it is desired to rotate the rod 10 .slightly in the initialloosening of thesame from lthe concrete, the rod 10' is provided withal1-opening extending therethrough and `which opening is designed to bealined with one ot the openings 21 in the head thus permitting theinsert-ion of the crow- Y end ot the member opposite the shank isreduced to forma relatively small bearing tube 25 upon which vis looselymounted a washer 26, one side of which is in bearing engagement with thehead and the opposite side of which constitutes a nut engaging surtace27. A nut- 28 is threaded on therod l() and inthe actuation ofthedevice'whenit is desired tomove the rod@longitudinallythis nut screwedup intofengagement witltthe washer.

In operation yand with' the mold boards removed, or even with Vthe moldboards in position, the jackie slippedon the projecting end of the rodand with the shank telescoped fully into the female member. The

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nut 28 is then screwed onto the rod until it is in bearing engagementwith the washer 26. 'Ihen by inserting the crow-bar into the opening 2lbut not into the opening the male member may be rotated in a directionto withdraw the same out of the female member and to yact through thewasher and nut to withdraw the rod longitudinally out of the setconcrete. v

In those situations where it is desired to rst loosen the rod by arotary movement thereof, the nut 28 is omitted and the crowbar passedentirely through the rod, so that with the rotation of the male memberthe rod will be unscrewed from the threaded concrete part and when therod is thus ini tially loosened the nut 28 may be screwed up intoposition as previously' suggested and the rod rapidly withdrawn by therotation of the male member. It is preferable from a mechanicalstandpoint to make the shank relatively short and as it approaches theoutward limit of its movement to rotate the same back into its collapsedposition, then rotate the nut into the advanced position to again engagethe washer and the operation is continued, and if necessary repeateduntil the rod is fully withdrawn from the Set concrete.

By means of a device of this character it is possible to remove the moldboards, so that on a given undertaking the amount of lumber utilized isreduced and withdrawing the rods without bending maintains the threadsthereon intact and permits the repeated use of the rod, Without thenecessity of straightening the same. The jack can be quickly installedin position and as there are but two screw parts, and these parts arenecessarily made quite rugged the possibility of distorting the partsthrough the excessive force necessary in such a situation is reduced toa minimum.

It is obvious that the jack illustrated may be utilized in otherlocations, for instance, where it is desired to draw on a rod or cable.As one illustration of such a use, it niay be noted that the ack couldbe mounted on a tripod and a lifting rod disposed vertically in place ofthe rod l0 or the jack could be mounted on a suspension bridge tower todraw the cables taut.

Having thus described my invention. I claim:

l. In a device of the class described, the combination with' a tie rodfor connecting the mold boards of a concrete form, one end of said rodwhich is designed to extend beyond the concrete being threaded andprovided with a hole extending transversely therethrough, of a `iackprovided with an opening extending axially therethrough for receivingthe threaded portion of the rod, said jack including a female bearingmember internally screw threaded and provided with a concrete engagingend, a male member provided with a massive head and a shank portion inthreaded engagement with the bearing member, said head provided with anopening extending therethrough and designed to be alined with theopening in the rod whereby a crow-bar or similar leverage tool may beinserted in said alined openings and the head and rod rotatedsimultaneously thereby to screw the rod out of the concrete.

Q. In a device of the class described, the combination with a tie rodfor connecting the mold 'boards of a concrete form, and provided with ahole extending transversely therethrough, of a jack provided with anopening extending axially therethrough for vreceiving a projectingport-ion of the rod, said ack including a female bearing memberinternally screw threaded and provided with a concrete engaging end, amale member provided with a massive head and a shank portion in threadedengagement with the bearing member, said head provided with an openingextending therethrough and designed to be alined with the opening in therod whereby a crow-bar or similar leverage tool may be inserted in saidalined openings and the head and rod rotated simultaneously thereby toloosen the adhesion between the rod and the concrete.

3. In a device of the class described. the combination with a tie rodfor connecting the mold boards of a concrete form, one end of said rod,which is designed to extend beyond the concrete, being threaded, of ascrew jack provided with a hole extending axially therethrough forreceiving the threaded portion of the rod, said jack including a femalebearing member internally screw threaded and provided with a concreteengaging end, a male member provided with a head adapted to be engagedby a rotating tool and provided with a shank in threaded engagement insaid female member and a nut in threaded engagement with said rod to theoutside of said male member whereby the rotation of said head in onedirection will move the same into bearing engagement with the nut andact thereon to draw the rod axially out of the lconcrete and withoutbending the rod, said nut adapted to be advanced on the rod.

4. In a device of the class described, the combination with a tie rodfor connecting the mold boards of a concrete form`r` one end of saidrod, which is designed to extend beyond the concrete, being threaded, ofa screw jack provided with a hole extending axially therethrough forreceiving the threaded portion of the rod,'said jack including a femalebearing member internally screw threaded and provided with a headadapted to be engaged by a rotating tool and provided with a shank inthreaded engagement in said female member, a nut in threaded engagementwith said rod to the outside of said male member whereby the rotation ofsaid head in one direction will move the same into bearing engagementwith the nut and act thereon to draw the rod axially out of the concreteand without bending the rod, said nut adapted to be advanced on the rod,and a washer loosely mounted on the male member and disposed between therevoluble head and the nut threaded on the rod.

5. In a device for withdrawing a tie rod from a concrete construction, ascrew jack Aformed of two parts, one of said parts constituting a femaleshort bearing member with one end enlarged to form a concrete engagingend designed to extend over an extensive area of the concrete and theother part constituting a male member provided with a head and a shankportion threaded finto said female member, said male member providedwith an opening extending axially therethrough and having a diameterdesigned to accommodate the rod acted upon and approximately to engagesaid rod to minimize any tendency of the rod to bend,

said head provided with means for receiv-` ing a leverage tool to rotatethe male mem- 'ber out of the female member.

6. A screw jack for withdrawing tie rods from concrete constructions,including a female Ibearing member with one end forming a concreteengaging end and having a bore of relatively large diameter extendingaxially therethrough, a shiftable rod guiding member provided with abore extending axially therethrough for accommodating the tie rod for adistance substantially equal to the length of the jack when collapsed,said guiding member provided centrally thereof with a head adapted to beengaged by a leverage tool to rotate the guiding member, a shank ofrelatively large diameter constituting a male member and fitted `in saidlarge diametered bore and in screw threaded engagement with said femalemember, a

bearing tube of relatively small external diameter extending from theside of the hea-d opposite the shank and a washer loosely mounted onsaid tube whereby the rod guid ing member may be rotated about the rodbeing withdrawn, relative to both the washer and the female member whilebeing withdrawn from the female member.

7. A screw jack for withdrawing tie rods from concrete constructionsincluding a female bearing member with one end enlarged to form aconcrete engaging end and having a relatively large bore extendingaxially therethrough and internally screw threaded, a male member havinga head adapted to be engaged by a tool to rotate the member and having ashank fitted in said large bore, externally screw threaded and engagingthe threads of the female member, said head and shank having a smoothbore extending axially therethrough and adapted substantially to engagethe rod along the entire length of the male member thereby to assist inminimizing any tendency of the rod to become bent during the withdrawalthereof` from the concrete.

8. A screw jack for withdrawing tie rods from concrete construction,comprising two threaded parts, one part constituting a female memberadapted to be held in yfixe/d position relative to the concretestructure and the other part constituting a coacting male memberthreaded into said female member, said `male member provided with a rodreceiving bore extending axially therethrough and a washer mountedloosely on said head at the end thereof oppositethe end in threadedengagement in the female member, the outer end of said washer providedwith a nut-engaging surface.

Q. In a device of the class described, the combination of a screw jackcomprising two threaded parts, one part constituting a female memberadapted to `be held in fixed position relative to the concreteconstruction and the other part constituting a coacting male memberthreaded into said female member, said male member provided with a rodreceiving bore extending axially therethrough and washer mounted looselyon said head at the end thereof opposite the end in threaded engagementin the female member, the outer end of said washer provided with a nutengaging surface and a nut adapted to be threaded on the rod and engagedby said nut engaging surface to withdraw the rod from the concrete whenthe male member is rotated in one direction.

Signed aft New York city, in the county of New York and State of NewYork this '27th day of November A. D. 1918.

ROBERT SHARP.V

k(Jolcl o! this patent mary be obtained for ve cents each, by addressingthe Commissioner of Intenta.

-Wnshington, D. c.

